The Laboratory for the Study of Behavioral Processes is dedicated to elucidating the associations of physical and mental health problems with everyday behavioral and emotional functioning. Previous activities of this lab have made important substantive and methodological contributions to the study of mental health in older people. Currently proposed activities will continue and extend those activities in keeping with the focus of the CRC on efficacy and effectiveness of interventions to treat and prevent mental disorders among older persons with co-morbid health problems. Specific aims of the Behavioral Processes Lab are: (1) to characterize the effective and behavioral concomitants of depression and other mental disorders among older persons with co-morbid medical illness, including dementia; (2) to identify affective and behavioral predictors of the development, course, and responsivity including dementia; (2) to identify affective and behavioral predictors of the development, course, and responsivity to treatment of late life mental disorders; (3) to develop and validate innovate behavioral methods for prevention and treatment of late life mental disorders, and (4) to develop and validate innovate methods and measures for evaluating the efficacy and the effectiveness of such interventions. The Behavioral Processes Laboratory will achieve these aims primarily through a series of focused research projects examining psychological, behavioral, and interpersonal processes associated with physical and mental health in late life. These studies focus on diverse populations, measures, and methods, but all deal with intrapersonal and interpersonal processes, leading to, or resulting from depressive illness among physically frail older persons. Specific projects proposed for this funding period include: (1) development and implementation of an intervention to facilitate adaptation to long-term residential care; (2) pilot research on everyday social support and quality of life during and following chemotherapy for breast cancer; (3) development and implementation of a treatment protocol for conducting psychotherapy with depressed older persons with dementia; (4) examination of coping and adaptation in end-stage renal disease, and (5) interrelated studies of daily interactions between two populations of chronically ill individuals and their family caregivers: Persons with AIDS of all ages, and cognitively intact, chronically ill older persons.